Split dart:builtin into dart:builtin and dart:io.

runtime/bin/main.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 #include "include/dart_debugger_api.h"
@@ skipping 221 matching lines @@
   if (tag == kCanonicalizeUrl) {
     // If this is a Dart Scheme URL then it is not modified as it will be
     // handled by the VM internally.
     if (is_dart_scheme_url) {
       return url;
     }
     // Create a canonical path based on the including library and current url.
     return DartUtils::CanonicalizeURL(NULL, library, url_string);
   }
   if (is_dart_scheme_url) {
-    return Dart_Error("Do not know how to load '%s'", url_string);
+    // Handle imports of dart:io.
+    if (DartUtils::IsDartIOLibURL(url_string) && (tag == kImportTag)) {
+      return Builtin::LoadLibrary(Builtin::kIOLibrary);
+    } else {
+      return Dart_Error("Do not know how to load '%s'", url_string);
+    }
   }
   result = DartUtils::LoadSource(NULL, library, url, tag, url_string);
   if (!Dart_IsError(result) && (tag == kImportTag)) {
-    Builtin::ImportLibrary(result);
+    Builtin::ImportLibrary(result, Builtin::kBuiltinLibrary);
   }
   return result;
 }
 
 
 static Dart_Handle LoadScript(const char* script_name) {
   Dart_Handle source = DartUtils::ReadStringFromFile(script_name);
   if (Dart_IsError(source)) {
     return source;
   }
@@ skipping 30 matching lines @@
     char errbuf[256];
     snprintf(errbuf, sizeof(errbuf),
              "Expected a library when loading script: %s",
              canonical_script_name);
     *error = strdup(errbuf);
     Dart_ExitScope();
     Dart_ShutdownIsolate();
     return false;
   }
   if (script_snapshot_buffer == NULL) {
-    Builtin::ImportLibrary(library);  // Implicitly import builtin into app.
+    // Implicitly import builtin into app.
+    Builtin::ImportLibrary(library, Builtin::kBuiltinLibrary);
   }
   if (snapshot_buffer != NULL) {
     // Setup the native resolver as the snapshot does not carry it.
-    Builtin::SetNativeResolver();
+    Builtin::SetNativeResolver(Builtin::kBuiltinLibrary);
+    Builtin::SetNativeResolver(Builtin::kIOLibrary);
   }
   Dart_ExitScope();
   return true;
 }
 
 
 static bool CaptureScriptSnapshot() {
   char* error = NULL;
   Dart_Handle result;
 
@@ skipping 234 matching lines @@
   Dart_ExitScope();
   // Dump symbol information for the profiler.
   DumpPprofSymbolInfo();
   // Shutdown the isolate.
   Dart_ShutdownIsolate();
   // Terminate event handler.
   EventHandler::Terminate();
 
   return 0;
 }